Parametric Plot
- To: mathgroup at smc.vnet.net
- Subject: [mg27077] Parametric Plot
- From: Winston Garira <uceswga at ucl.ac.uk>
- Date: Sat, 3 Feb 2001 04:59:12 -0500 (EST)
- Sender: owner-wri-mathgroup at wolfram.com
I am trying to solve a system of two coupled pendulums using the NDSolve.
command. If I replace the Plot[{xd[t],xr[t]},{t,0,100}] with
ParametricPlot[{xd[t],xr[t]},{t,0,100}] it does not work. Can someone tell
me why the ParametricPlot command does not work in this case. I need to
make parametric plots for this system.
Thanking you in annticipation
Winston
Pends[init1_, init2_, time_, k_, {c_, w_, p_}]:=
Module[{},
pend=NDSolve[{x1''[t]+ c x1'[t]+ p Sin[x1[t]]==k(x2[t]-x1[t]),
x2''[t]+ c x2'[t]+ p Sin[x2[t]]==k(x1[t]-x2[t]),
x1[0]==init1[[1]], x1'[0]==init1[[2]],
x2[0]==init2[[1]], x2'[0]==init2[[2]]},
{x1, x2},
{t,0,time}, MaxSteps->200000];
xd[t_] := Evaluate[x1[t] /. pend];
xdd[t_]:= Evaluate[x1'[t] /. pend];
xr[t_] := Evaluate[x2[t] /. pend];
xrd[t_]:= Evaluate[x2'[t] /. pend];
];
c=0.1; w=0.5; p=1.9;
Pends[{1.57,0}, {-1.57,0}, 5000,0.6, {c,w,p}];
Plot[{xd[t],xr[t]},{t,0,100},
PlotStyle\[Rule]{RGBColor[1,0,0.3],RGBColor[0,0.5,1]}];
W.GARIRA
E-mail: w.garira at ucl.ac.uk
phone : +44-(0)20-7679-2521
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